To enhance the quality perception of a mobile terminal (such as a mobile phone or a tablet), metal is increasingly applied to industrial design of mobile terminals. Such industrial design significantly affects antenna performance. Using a mobile phone as an example, wireless communication is a mandatory function of the mobile phone, and an antenna is a mandatory component of the mobile phone. The level of antenna performance is also important to multiple aspects, for example, whether call quality is good and whether a data service is smooth. In industrial design with various metal materials, design of an antenna with a metal rear cover is the most challenging. A rear cover is a rear housing of a mobile terminal. A metal rear cover is a metal rear housing.
As shown in FIG. 1, a technical solution in the prior art is that a metal rear cover is fully split into three parts or at least two parts, and adjacent parts are fully separated by a gap 10′. By setting a width of the gap 10′ to a relatively small value, a shape of the metal rear cover can be well ensured. Then one part of metal 11′ obtained by splitting directly serves as a part of the antenna. The gap 10′ may be filled with a bond that is used to bond all parts of the metal rear cover into an entirety. As described above, radiation of the antenna requires an open environment. If the part separated from the metal rear cover is used as a part of the antenna, the outside of the metal rear cover is air. Due to the electrical characteristics of air, air is also an open medium to the antenna. Therefore, the antenna is free from a problem that the open environment is damaged. However, a tail end of the antenna (or called an opening end of the gap 10′) is generally on a lateral edge of the mobile phone, and the gap 10′ tends to be held by a hand of a user. Once this place is held by a hand, an operating resonance of the antenna is deviated massively, and performance is deteriorated as a result. In an antenna reflection coefficient test diagram shown in FIG. 2, an operating frequency of an antenna is deviated by hundreds of megahertz (MHz) depending on presence of a finger, which indicates great impact and leads to a poor communication effect of the mobile phone.